DUBUQUE, Iowa (AP)  Republican presidential challenger Mitt Romney is pushing to win a band of Midwestern states that voted for President Barack Obama four years ago and that generally have a long history of backing Democrats in White House elections.

Romney faces hurdles and advantages in each state but his approach will leave Obama no choice but to spend time and money defending states he carried in 2008. That Romney is even making a making a play for the arc of states from Pennsylvania to Iowa also suggests his path to the 270 electoral votes he will need to win the White House may be widening.

"It's sending a pretty clear message that the places the Democrats have taken for granted, they can't take for granted this time," said Rich Beeson, Romney's political director.

Before arriving in Iowa on Monday, Romney stopped in Janesville, Wis., an economically struggling, one-time manufacturing hub in the southern part of the state. Unemployment there is 9 percent, well above the state average of 6.8 percent for May. The national average is 8.2 percent.

He toured Monterey Mills, a unionized company that makes fabric for paint rollers and the stuffing for toys like Winnie the Pooh.

"The people of this country are having a hard time. These are challenging times for Americans, and because of his failed record his campaign is having a hard time deciding what to talk about," Romney said, the excited crowd sitting amid packages of fabric the company uses to make its paint rollers.

Wisconsin, which has not backed a Republican for president since Ronald Reagan in 1984, presents a new opportunity for Romney, almost exclusively due to Gov. Scott Walker's triumph two weeks ago in a contentious recall election. Walker's win, after an 18-month fight over public employee union rights, gives Republicans hope. It also gives Romney a corps of well-trained organizers and reams of voter data to put to use.

But he still has his work cut out for him. Voters said in exit polls after the June 5 election that they trust Obama more to address the nation's economic struggles  the chief argument for Romney, a former businessman  and the interests of the middle class.

Obama also continues to have the advantage in urban areas, especially among minority voters, which each state except Iowa has.

"Philadelphia is a gigantic amount of the vote," said Tad Devine, a top aide to Democratic presidential nominees in 2000 and 2004. "Pennsylvania is one of those places that may stay competitive longer, but it's going to be really hard for Romney to put together Pennsylvania if Philly turns out the way it can turn out."

Iowa, however, has trended Republican since Obama won it in 2008. Like nearly every state in the arc, Iowans turned down Democratic candidates for governor in favor of pro-business Republicans. Iowa voters dumped three state Supreme Court justices to protest their decision allowing gay marriage. Romney's campaign also spent the year before the state's leadoff nominating caucuses laying the foundation in this true swing state for a general election campaign. Iowa has voted Republican in every other presidential election since 1988.

Obama, meanwhile, enjoys a special Iowa connection, having won the 2008 Democratic caucuses in Cinderella fashion. He's already built a robust ground operation. He has spent nearly $5 million on advertising in Iowa, and has spent no money in Wisconsin since early in the year.

Although Romney aides say there is no Midwestern lynchpin, they argue that a competitive streak in Wisconsin is good for them in the entire region.

On Monday, he followed in the footsteps of Republican George W. Bush, who campaigned hard for re-election in Iowa in part by seeking to connect with working-class voters along the Mississippi River who haven't warmed to Obama.

Romney headed south along the Mississippi to Davenport, Iowa, aboard the Spirit of Dubuque, and into the heart of the region where Bush worked to trim Democratic margins in his 2004 re-election and narrow win in Iowa. The trip was part of a five-day bus tour that is taking Romney across six states: New Hampshire, Pennsylvania, Ohio, Wisconsin, Iowa and, on Tuesday, Michigan.

"There's a reason he's in eastern Iowa," said Ben Lange, a Republican challenging Democratic Iowa Rep. Bruce Braley. Lange appeared with Romney on the boat in Dubuque.

Obama lost white, non-college-educated voters to Republican John McCain in 2008, according to exit polls. These voters made up nearly half of all Midwestern voters, more than any other region. Obama had support from 46 percent of these voters in the Midwest, compared to McCain's 52 percent. Nationally, the group split 40 percent for Obama, 58 percent for McCain.

Recent polling by Associated Press-GfK suggests Obama is underperforming his 2008 showing in this group. In a May survey, just 31 percent of white non-college-educated adults in the Midwest said they backed Obama, compared with 57 percent who said they supported Romney. The May poll showed Obama faring better nationally, but still trailing Romney 38 percent to 53 percent.

The population in Democratic-controlled Detroit has fallen sharply, by 25 percent in the last decade, and Detroit's Democratic voter turnout operation has also eroded some due to political struggles of the party-controlled mayor's and Wayne County executive's offices. The problems "really put a strain on the Democratic infrastructure," said Stu Sandler, former Michigan Republican Party executive director.

Romney is sure to face continued criticism by Obama and his allies for opposing the automotive industry bailout, which the president credits with saving Detroit and buoying car-related manufacturing in nearby Ohio.

Turnout in these small manufacturing towns will decide how competitive Romney will be against Obama in Pennsylvania. But even Democrats acknowledge the fight might be tougher than it appears, considering no Republican has won here since 1984.

"It's going to be a close race in Pennsylvania," said former Rep. Patrick Murphy, a Democrat from suburban Philadelphia.

Romney took a different tack in Ohio, which is dominated by large regional metro areas more so than the other states on the tour.

Instead of focusing just on small towns and cities, Romney's Ohio leg of the tour took him to areas just outside major metro areas of Cleveland and Columbus.

"Because they have so many big cities, they have so many suburbs," and fewer working-class voters, said Katie Gage, Romney's deputy campaign manager.